Perovskite/GaN-Based Light-Modulated Bipolar Junction Transistor for High Comprehensive Performance Visible-Blind Ultraviolet Photodetection

The state-of-the-art visible-blind ultraviolet (UV) photodetectors (PDs) are generally demonstrated to have typical photoconductor or photodiode structures, without the tunability to balance different photosensing parameters. Here, we propose a specially designed perovskite/GaN-based light-modulated bipolar junction transistor (BJT) for visible-blind UV photodetection. As the conduction-band-aligned p-n-p junction at the CH3NH3PbCl3/GaN interface dominates the photocarrier dynamics, the saturated photocurrent collected with the electrodes on the perovskite film is linearly dependent on the optical power pumped on the GaN film with multiplication. This device reaches a saturated output at 0.5 V, reporting a responsivity of 0.43 A/W, a specific detectivity of 4.11 × 1012 Jones, a rise/fall time of 70.50/71.83 μs, and the highest linear dynamic range of 159 dB. Our device provides a structure panel to optimize the trade-off between responsivity and response speed, with a comprehensive performance outperforming the published similar UV PDs and commercial products. Moreover, it can be readily integrated with GaN-based lighting devices for full-duplex communication in light-fidelity (LiFi) networks.